The fire occurred July 18 at about 2:34 a.m. at The Law Offices of Tad Nelson & Associates on East Main Street, according to city officials.
The League City Fire Marshal's Office released video of the person arriving to the office in a red sports-style motorcycle.
They were wearing dark long-sleeved outerwear, light-colored pants, and a light-colored backpack.
If you know any information on who the person may be, you are urged to call Deputy Bass at 281-554-1297.
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